There are many instances in which a person must undergo body fluid sampling. Medical practitioners often require full blood analyses to assist in the diagnosis of a disease or condition. Diabetics, for example, must monitor their blood sugar a number of times a day. The removal or blood from a human body is normally performed invasively and tends to be painful, leading to procrastination and non-compliance of the patients. Moreover, in children and babies, the invasive procedures are more difficult and less effective. There is therefore a need to develop both less painful invasive procedures and non-invasive procedures for blood and other body fluid removal.
Some devices and methods for invasive blood sampling are described in the art, inter alia, U.S. Pat. No. 6,045,567 describes a lancing device, having a spring-loaded lancet holder slidably mounted within a housing for carrying a disposable lancet and needle. A knob on the back of the device has forward-extending fingers that stop the lancet holder at an adjustable predetermined point after the device has been fired. The fingers not only control the penetration depth of the needle, but also absorb vibrations and reduce noise to cause less pain to the user.
US 2005/038463 describes a device for providing transcutaneous electrical stimulation (TENS) to the finger of a patient at the same time that the finger is being punctured for the purpose of obtaining a blood sample. The device should reduce the pain associated with this procedure and should be of particular interest to diabetic patients that must perform repeated finger puncture procedures to monitor blood glucose levels.
US 2005/234486 describes an apparatus for extracting bodily fluid (e.g., whole blood) from a user's finger includes a housing with a lancing mechanism and a clamping mechanism attached to thereto. The clamping mechanism includes a lower arm assembly and an upper arm assembly. The upper and lower arm assemblies are operatively connected such that when a user's finger applies a user force to the lower arm assembly and displaces the lower arm assembly from a first to a second position, the upper and lower arm assemblies cooperate to engage the user's finger with a compressive force that is greater than the user force. In addition, the lancing mechanism is configured to lance a target site on the user's finger while the upper and lower arm assemblies are cooperating to engage the user's finger. Thereafter, the compressive force serves to extract a bodily fluid sample from the lanced target site.
US 2006/224085 describes a method for collecting small amounts of blood sample by painless puncture of a finger. When puncture of skin of a human being by a needle or another device is performed at the depth of no more than 0.5 mm, pain accompanied by the puncture is diminished or decreased. Regardless of an error in the depth of the puncture, the depth of puncture always needs to not exceed this depth. The site of puncture is the dorsal surface of a finger, that is, the area from finger joint (IP joint of thumb, DIP joint of fingers other than thumb) to proximal nail wall and the area extending from proximal nail wall to lateral nail wall.
Some devices and methods for non-invasive blood sampling are described in the art, inter alia, U.S. Pat. No. 6,400,972 describes an over-systolic pressure, which is applied to a patient's blood perfused fleshy medium. The pressure causes a state of temporary blood flow cessation within a time period insufficient for irreversible changes in the fleshy medium. Release of the over systolic pressure causes a state of transitional blood flow terminating with the normal blood flow. At least two sessions of measurement, separated in time, are executed and at least one of these sessions is selected within the time period including the state of temporary blood flow cessation and the state of transitional blood flow. Optical non-invasive measurement of the concentration of at least one blood constituent are successively performed at these at least two sessions, and respective values of the concentration are obtained.
US 2004/249252 describes a method and device for use in non-invasive optical measurements of at least one desired characteristic of patient's blood. A condition of artificial blood kinetics is created at a measurement location in a patient's blood perfused fleshy medium and maintained for a certain time period. This condition is altered over a predetermined time interval within said certain time period so as to modulate scattering properties of blood. Optical measurements are applied to the measurement location by illuminating it with incident light beams of at least two different wavelengths in a range where the scattering properties of blood are sensitive to light radiation, detecting light responses of the medium, and generating measured data indicative of time evolutions of the light responses of the medium for said at least two different wavelengths, respectively, over at least a part of said predetermined time interval.
US 2007/043281 describes a method and system for non-invasive measurements in a patient's body in which several measurement sessions are performed on a measurement location. Each measurement session includes applying an external electromagnetic field to the measurement locations, detecting at least two responses of the measurement location, and generating data indicative of the detected response. These responses are characterized by at least two different values of a controllable parameter. The measurement sessions include at least two measurement sessions carried out at a normal blood flow in the measurement location and at least two measurement sessions carried out at a condition of artificial kinetics in the measurement location. The first and second measured data are processed to determine a first relation between the first time variations and a second relation between the second time variations for the different parameter that can be used to determine the at least one blood related parameter.
US 2008/262324 describes an efficient approach of attaching and fixing a measurement head for a spectroscopic system to a variety of different parts of the skin of a patient. The measurement head preferably features a compact design providing a flexible handling and offering a huge variety of application areas taking into account the plurality of properties of various portions of the skin. Furthermore, the measurement head features a robust and uncomplicated optical design not requiring a lateral shifting of the optical axis of the objective. Such transverse relative movements between the objective and a capillary vessel in the skin are preferably performed by mechanically shifting the skin with respect to the objective of the measurement head. Moreover, the measurement head is adapted to host one or more pressure sensors measuring the contact pressure between the measurement head and the skin. This pressure information can further be exploited in order to calibrate the spectroscopic analysis means, to regulate the contact pressure within predefined margins specifying an optimum range of contact pressure for spectroscopic examination of capillary vessels.
Most of the non-invasive devices in the art require occasional calibration involving invasive blood sampling. There is therefore a need to provide systems, devices and methods for blood sampling which overcome the limitations and disadvantages of the devices and methods described hereinabove.